Do we have free will? Is the universe compatible with God? Do we live in a computer simulation? Does the universe think? Physicists are great at complicated research, but they are less good at telling us why it matters. In this entertaining and groundbreaking book, theoretical physicist Sabine Hossenfelder breaks down why we should care. Drawing on the latest research in quantum mechanics, black holes, string theory and particle physics, Existential Physics explains what modern physics can tell us about the big questions.